1. Field of the Invention
The present invention relates to a liquid crystal display device for performing an image display by interposing a liquid crystal between two substrates and a method of manufacturing the same.
2. Description of the Related Art
In FIG. 9A, there is shown a plan view of an active matrix type TFT liquid crystal display device utilizing thin film transistors (TFTs) as switching elements and, in FIG. 9B, a plan view of a main portion centering around a chamfering area A2 in an end portion of substrate constituting the liquid crystal display device. In this liquid crystal display device, a liquid crystal material is interposed between a 1st substrate 101 and a 2nd substrate 102, plural signal wirings 103 and plural scan wirings 104 are formed on the 1st substrate 101, TFTs and pixel electrodes are connected to positions where the signal wirings 103 intersect the scan wirings 104, and an image is displayed by means of controlling an orientation of the liquid crystal material by driving the TFTs. A1 shows a display area.
The 1st substrate 101 is produced with its dimension being made somewhat larger than the 2nd substrate 102, a connecting terminal portion (general term for signal wiring connecting terminals 105 and scan wiring connecting terminals 106) is formed in the signal wirings 103 and the scan wirings 104, which are extended outside the 2nd substrate, and it is connected to an external driving circuit at this connecting terminal portion. In addition, the reference numeral 107 denotes chamfering amount marks formed as marks showing chamfering upper and lower limits when a chamfering work is performed to an end portion at a side, of the 1st substrate 101, where the connecting terminal portion is formed, 109 an extension wiring extended from the signal wiring 103 or the scan wiring 104, and 110 a short wiring which is formed in the end portion of the 1st substrate 101 to be chamfered and is electrically connected to the plural extension wirings 109.
In a cell assembling process for superposing the 1st substrate 101 and the 2nd substrate 102 facing the former and injecting the liquid crystal, in order to orient the liquid crystal material, there is required such a process as rubbing polyimide films (orientation films) applied to the 1st substrate 101 and the 2nd substrate 102 with a cloth, but in this process there is a case that a very strong static electricity is generated, and thus an overvoltage is applied to the scan wirings 104 and the signal wirings 103, so that a line defect is generated by a deterioration of the TFT on the wirings, and the like. As a countermeasure for preventing such a line defect, there has been known a method in which the short wiring 110 for short-circuiting the signal wirings 103 and the scan wirings 104 is disposed in the vicinity of the substrate end portion and, before a lighting inspection process, the short wiring 110 is excised by a chamfering work of an end face.
However, there is a case that the short wiring 110 generates an elimination badness owing to a dispersion in chamfering amount and the like and, in this case, a short circuit between the adjoining wirings occurs, so that there has been a problem that a display badness such as the line defect and a breakage of an inspection driving circuit occur. Further, reversely, in case where the chamfering amount is set large in order to prevent the elimination badness, there have been problems that it takes a time to perform the chamfering work, so that a cost is increased and, besides, a terminal connecting portion and the like are resected.
Further, on the other hand, since the liquid crystal display device is used in a note type personal computer, a portable terminal and the like, it is strongly demanded to lighten them and narrow their frames. As one means for meeting these demands, there is a method of economizing a chamfering region by reducing the chamfering amount in a panel end. In this case, it is required to improve a chamfering accuracy than former times and, in order to realize an improvement in the chamfering accuracy without incurring a cost, there must be established a method of accurately process-controlling the chamfering amount in a usual manufacturing process.
In order to solve such problems of the elimination badness prevention and the chamfering amount reduction as mentioned above, as disclosed in Japanese Patent Laid-Open No. 278514/1996 Gazette, there has been known a method in which marks showing a chamfered state are formed. As shown in FIG. 9B, it is shown that, in this method, patterns of the chamfering amount marks 107 showing the chamfered state are disposed/formed on a position which is a lower limit position of the chamfering amount and shows a necessary minimum limit region, including the short wiring 110, to be chamfered and a position which is an upper limit position of the chamfering amount and shows a region not to be chamfered, and it is possible to easily prevent the elimination badness of the short wiring 110 and an excessive chamfering amount by means of performing a work while confirming, by visual observation, the mark portions in the chamfering process. Further, it is mentioned about the fact that, by means of controlling the chamfering amount by using the chamfering amount marks 107, a dispersion of the chamfering amount can be easily and accurately grasped, so that the chamfering accuracy can be improved without a new equipment investment.
However, generally, when forming the chamfering amount marks 107, in order to avoid adding a new process for forming the chamfering amount marks 107, a conductive thin film such as mainly Cr and A1 is used because a thin film layer existing on the 1st substrate 101 is concurrently used. Accordingly, in case where the chamfering amount marks 107 are formed independently of another conductive pattern, a pattern of the chamfering amount marks 107 is electrified by a static electricity generated in a manufacturing process such as cell assembling process, so that there have been such risks that an electric discharge occurs in a later process and thus the chamfering amount marks 107 and patterns of insulation film and conductive film in the vicinity thereof are damaged and, additionally, that a display badness such as the line defect occurs by the fact the scan wirings 104 and the signal wirings 103, which exist near to the chamfering amount marks 107, are damaged.
In case of avoiding such electric discharge troubles as mentioned above, although there is considered a countermeasure that the pattern of the chamfering amount marks 107 is made an insulation film, since it is necessary to use an opaque material in order to possess a function as the marks, an insulation material such as silicon nitride used on the 1st substrate 101 cannot be concurrently used, so that a new process for forming the chamfering amount marks 107 becomes necessary, thereby leading to an increase in cost.
The invention has been achieved in order to solve such problems of the prior art as mentioned above, and its object is to provide a display device capable of reducing its cost, lightening its weight and narrowing its frame by preventing a reduction in process yield owing to the display badness resulting from the static electricity generated in a conductive pattern becoming the chamfering amount marks and by reducing the chamfering amount.
The invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a conductive chamfering amount mark provided on the 1st substrate and used as a mark when chamfering the 1st substrate is constituted by a mark pattern disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate and a connecting wiring connected to the mark pattern, and the chamfering amount mark is left contacting with a chamfered end portion of the 1st substrate.
Further, the invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a conductive chamfering amount mark provided on the 1st substrate and used as a mark when chamfering the 1st substrate is constituted by a mark pattern disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate and a connecting wiring for connecting the mark pattern to a conductive wiring formed on the 1st substrate.
Additionally, the invention provides a liquid crystal display device wherein, in such a constitution as mentioned above, the conductive wiring and the chamfering amount mark are formed in one continuous pattern.
Further, the invention provides a liquid crystal display device wherein, in such a constitution as mentioned above, the mark pattern and the connecting wiring are disposed through a transparent insulating film and electrically connected in a contact hole opened in the transparent insulating film.
Additionally, the invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a chamfering amount mark provided on the 1st substrate and used as a mark when chamfering the 1st substrate is constituted by a conductive pattern having a mark pattern disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, and a conductive wiring formed on the 1st substrate and the conductive pattern are electrically connected at a mutually superposed position.
Further, the invention provides a liquid crystal display device wherein, in such a constitution as mentioned above, the mark pattern is constituted by a different conductive pattern or a punched pattern.
Additionally, the invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a chamfering amount mark used as a mark when chamfering the 1st substrate is constituted by end portions of conductive wirings formed on the 1st substrate, and an electrically connectable mark pattern connecting, in a ladder-like form, between the plural adjoining conductive wirings is disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering.
Further, the invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a chamfering amount mark provided on the 1st substrate and used as a mark when chamfering the 1st substrate is constituted by an end portion of a conductive wiring formed on the 1st substrate, and a mark pattern connecting, in a ladder-like form, between branch wirings of the conductive wiring whose tip has been branched is disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering.
Additionally, the invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a chamfering amount mark provided on the 1st substrate and used as a mark when chamfering the 1st substrate is constituted by bending an end portion of a conductive wiring formed on the 1st substrate, and a mark pattern consisting of a bent portion in which the conductive wiring has been bent is disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering.
Further, the invention provides a liquid crystal display device in which a liquid crystal is interposed between a 1st substrate and a 2nd substrate, wherein a chamfering amount mark provided on theist substrate and used as a mark when chamfering the 1st substrate is constituted by changing, at a predetermined interval, a wiring width of an end portion of a conductive wiring formed on the 1st substrate, and a mark pattern consisting of a wiring width changed portion in which a width of the conductive wiring has been changed is disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering.
Additionally, the invention provides a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate, forming a short wiring for mutually electrically connecting the plural conductive wirings in the vicinity of an end portion of the 1st substrate, and further forming a chamfering amount mark constituted by mark patterns electrically connected to the short wiring or the conductive wirings and disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, and by a connecting wiring for mutually electrically connecting the plural mark patterns, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference, thereby excising the short wiring.
Further, the invention provided a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate, forming a short wiring for mutually electrically connecting the plural conductive wirings in the vicinity of an end portion of the 1st substrate, and further forming a chamfering amount mark constituted by mark patterns electrically connected to the conductive wirings and disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, and by a connecting wiring for mutually electrically connecting the mark patterns to the conductive wirings, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference, thereby excising the short wiring.
Additionally, the invention provided a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate and forming a short wiring for mutually electrically connecting the plural conductive wirings in the vicinity of an end portion of the 1st substrate, a process for forming a chamfering amount mark constituted by mark patterns electrically connected to the short wiring on the 1st substrate and disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, and by a connecting wiring superposed with the mark patterns through a transparent insulating film, performing an electric connection to the mark patterns in a contact hole opened in the transparent insulating film, and mutually electrically connecting the plural mark patterns or electrically connecting the mark patterns to the conductive wirings, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference, thereby excising the short wiring.
Further, the invention provided a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate and forming a short wiring for mutually electrically connecting the plural conductive wirings in the vicinity of an end portion of the 1st substrate, a process for forming a transparent insulating film on the 1st substrate including surfaces of the conductive wirings, a process for forming a contact hole in the transparent insulating film positioned on the conductive wirings, a process for forming a chamfering amount mark constituted by conductive patterns including, on the transparent insulating film, mark patterns disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, and performing an electric connection between the conductive wirings and the chamfering amount mark in the contact hole, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference, thereby excising the short wiring.
Additionally, the invention provided a method of manufacturing a liquid crystal display device, comprising a process for forming a chamfering amount mark constituted by conductive patterns including, in the vicinity of an end portion to be chamfered of a 1st substrate, mark patterns disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, a process for forming a transparent insulating film on the 1st substrate including a surface of the chamfering amount mark, a process for opening a contact hole in the transparent insulating film positioned on the chamfering amount mark, a process for forming conductive wirings on the transparent insulating film and, at the same time, forming a short wiring for mutually electrically connecting the plural conductive wirings in the vicinity of the end portion of the 1st substrate, and performing an electric connection between the conductive wirings and the chamfering amount mark in the contact hole, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference, thereby excising the short wiring.
Further, the invention provided a method of manufacturing a liquid crystal display device, wherein, in such a constitution as mentioned above, the mark pattern is formed by a different conductive pattern or a punched pattern.
Additionally, the invention provides a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate, and forming a chamfering amount mark which is constituted by end portions of the conductive wirings and in which an electrically connectable mark pattern connecting, in a ladder-like form, between the plural adjoining conductive wirings is disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference.
Further, the invention provides a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate, and forming a chamfering amount mark which is constituted by end portions of the conductive wirings and in which a mark pattern connecting, in a ladder-like form, between branch wirings of the conductive wiring whose tip has been branched is disposed in a reference position consisting of at least any of a center, an upper limit and a lower limit of chamfering, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference.
Additionally, the invention provides a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate, and forming a chamfering amount mark which is constituted by end portions of the conductive wirings and in which a bent portion is provided in a reference position constituted by bending an end portion of the conductive wiring and consisting of at least any of a center, an upper limit and a lower limit of chamfering, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference.
Further, the invention provides a method of manufacturing a liquid crystal display device, comprising a process for forming conductive wirings on a 1st substrate, and forming a chamfering amount mark which is constituted by end portions of the conductive wirings and in which a wiring width changed portion is provided in a reference position in which a wiring width of the end portion of the conductive wiring has been changed at a predetermined interval and which consists of at least any of a center, an upper limit and a lower limit of chamfering on the 1st substrate, a process for bonding the 1st substrate after an orientation treatment and a 2nd substrate and injecting a liquid crystal, and a process for performing the chamfering with the chamfering amount mark provided on the 1st substrate being made a reference.
Additionally, the invention provides a method of manufacturing a liquid crystal display device, comprising, in such a constitution as mentioned above, a process for, when forming the conductive wirings on the 1st substrate, simultaneously forming a short wiring electrically connecting to the conductive wirings in the vicinity of an end portion of the 1st substrate, and a process for, when performing the chamfering with the chamfering amount mark being made a reference, simultaneously excising the short wiring.